tommi59 wrote:A question how close is the planet to hz of the star?is not in?

Host star's luminosity is nearly 9 times that of the Sun (HZ=ca. 3 AUs), so the planet receives at 9.55 AUs as much irradiation as if located 3.2 AUs away from a Solar-type star. So it is quite a Jovian planet. This could be favourable to inner and lower-mass planets, from Neptune to Earth-sized.

The transit is an intriguing possibility but I think next passage in front of its star should happen in 2015, I am not sure. It would be the transiting planet with the longest orbital period.

Also, is this a good candidate for looking for exo-moons? With a "bit" of luck a large moon may cause a dip in the planet's brightness. Also the transit curve , if transits pan out, may also give clues to moons or rings.

tesh90 wrote:Also, is this a good candidate for looking for exo-moons? With a "bit" of luck a large moon may cause a dip in the planet's brightness. Also the transit curve , if transits pan out, may also give clues to moons or rings.

I believe so. If not by their transit across the planet (which could be inflated, having recently formed, making things harder), then by the transit of its moons across the star. There's also the possible (likely?) presence of a circumplanetary disk which could complicate things.

Oh that's nice, also good to see that the inclination is consistent with that of the inner disc (as would be expected if the planet is responsible for the warp). Also interesting to see how it is matching up with the predictions for the planet being responsible for the cometary activity.

I really hope someone's measuring the reflex orbit of the star as well for this system... getting a dynamical mass would be extremely useful for the theoretical models!

Summary:β Pic b may not be in the main disk, but in the inclined disk. HARPS RV constrains the maass to less than 25 Jupiter-masses if orbiting within 12 AU. Orbit is still consistent with being responsible for the 1981 transit-like event.

Dusty atmosphere? Higher mass? Furthermore the updated astrometric measurements constrain the orbit further, and it continues to be consistent with a transiting orbit.

We also confirm that the putative transit date of Nov. 1981 claimed by Lecavelier Des Etangs & Vidal-Madjar (2009) could still be due to Beta Pictoris b, as the quoted date still falls in a peak of the distribution. Meanwhile, our analysis predicts a possible next transit in 2018, which will deserve to be tentatively observed.

Unfortunately I don't have the equipment to do these kind of observations so I don't know whether it would actually be feasible. I'd guess the length of the transit would make the stability of the equipment an issue.

I recently purchased a 14-inch dobsonian reflector that I intend to observe extrasolar planet transits with once I get a camera. But the major concern I would have is the transit window being obscenely long.

Hopefully it will be possible to narrow it down a bit before 2018, though in some ways the long transit window was why I was thinking of amateur involvement... no way would you be able to tie up a major telescope for that long!

This would have implications for the masses of the directly-imaged substellar objects in the group, including Beta Pic b:

Similarly, based on an age of 12+8−4 Myr, Bonnefoy et al. (2013) estimate a mass of 10+3−2 MJup for β Pic b, the uncertainties largely arising from the assumed age. Again, an increase in age to 21 Myr results in a 30 per cent increase in inferred mass, which is however still below the upper limit of 15.5 MJup currently imposed by dynamical constraints (Lagrange et al. 2012).

« …“This clump is an important clue to what is going on in the outer reaches of this young planetary system,” says Mark Wyatt, an astronomer at the University of Cambridge, UK, and a co-author on the paper. He goes on to explain that there are two ways such a clump can form: “Either the gravitational pull of an as yet unseen planet similar in mass to Saturn is concentrating the cometary collisions into a small area, or what we are seeing are the remnants of a single catastrophic collision between two icy Mars-mass planets”.Both of these possibilities give astronomers reason to be optimistic that there are several more planets waiting to be found around Beta Pictoris. “Carbon monoxide is just the beginning — there may be other more complex pre-organic molecules released from these icy bodies,” adds Roberge… »